Год выпуска: 2013 Автор: Peyman Sahebsara Издательство: LAP Lambert Academic Publishing Страниц: 152 ISBN: 9783659411595
Описание
The variational cluster approximation, based on the self-energy functional theory for electrons, is one of the quantum cluster methods, we introduced to investigate the broken symmetry states of strongly correlated systems. Layered organic compounds, in which dimers of organic molecules form an anisotropic triangular lattice, are among materials that show frustration. We discuss the two-dimensional one-band Hubbard model used for studying these compounds. A comparison of the normal state and Neel antiferromagnetic ordered phase energies, enables us to conclude that this order is dominant at large values of electron interactions. Moreover, various pairings of d-wave superconductivity is discussed in relation with cluster and lattice point group symmetries. No evidence of homogeneous coexistence of antiferromagnetic and d-wave superconducting phases is found. We also investigate a spiral magnetic order on the isotropic triangular lattice, where no Neel antiferromagnetic order is found....
